Fig. 6

RUNX3 transcriptionally downregulates Suv39H1 expression. A Suv39H1 mRNA levels in 55 LUAD tissues and paired noncancerous lung tissues were detected by qRT-PCR. B Protein expression of Suv39H1 in 4 pairs of clinical LUAD specimens. N and T mean adjacent normal tissue and paired lung cancer tissue, respectively. C qRT-PCR and western blot analysis of Suv39H1 expression in HBE and LUAD cell lines. D qRT-PCR analysis of Suv39H1 expression in A549 and H1299 cells after MEX3C knockdown. E Western blot analysis of MEX3C, RUNX3, and Suv39H1 expression in A549 and H1299 cells transfected with si-MEX3C and/or si-RUNX3. F, G The binding motif of RUNX3 was obtained from JASPAR dataset. Two binding sites for RUNX3 in the Suv39H1 promoter were also predicted by using JASPAR. H Assessment of the Suv39H1 promoter RUNX3 binding site via dual luciferase reporter assay. I RNA pull-down assay was performed to determine whether RUNX3 targets Suv39H1. J ChIP assessment of RUNX3 binding to the Suv39H1 promoter. Immunoprecipitation from A549 and H1299 cells using RUNX3 antibody or mouse immunoglobulin G (IgG). Bars represent mean ± SD from 3 independent experiments. *P < 0.05, **P < 0.01